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Friday, July 17, 2015

3DHS Extra SHP__Lightning strikes

Today was a big day for my new Extra SHP and also my new Thunder Power 3s 2250 55C Lightning battery packs. The Lightning series is very competitively priced, and work well in my 60" planes. Since the Extra SHP can fly well on something as small as a 3s 2250 pack, putting Lightning packs in one was an ideal combination.

The Excuse Paragraphs
The day did not go as well as I had planned, though. Like almost everyone else, I've been finding financing a bit tight lately. As such, I was forced to use a lot of equipment from my recently crashed Yak, otherwise known as "El Diablo." It turns out that crashing El Diablo was the best thing I ever did because all the gear was absolutely beat.

That plane had hundreds and hundreds of deliberate beat downs on it, plus dozens of hard hits, repairs, and even more beating down. Very simply, once I broke the plane a few times I decided to simply abuse it and see how long it lasted, which considering the treatment was well beyond considerable.

Unfortunately the crash damaged the bearings in the motor, and it was down on power a little, and also running hot. Down on power and running hot are not two things you normally associate with a Torque 2814, but this motor was driven straight into the ground at full throttle and full speed. It's also got hundreds of flights in my Yaks, and Lord knows how long I had it before that. Torques are sort of interchangeable to me. A five year old is as good as a new one to me, so I never keep track of when I bought motors or what plane they have been in. I just hammer them hard and am still waiting for one to blow up, which may never happen.

If nothing else, considering how gnarly the motor was sounding because of the bearings, it's amazing the thing ran as well as it did without blowing up.

At the end of the day the elevator servo started jittering at center. I changed the servos about five times and still had the problem, changed transmitter and even the extensions and still had a jumpy elevator. Finally in desperation I pulled the receiver out of my #2 Edge and that fixed it.

I thought I was having a case of new plane jitters and not flying that well, but now I am certain the receiver was giving me trouble. I traced the Yak crash to a fried rudder servo extension, and I can only guess since that was a dead short it probably affected the rest of the components. Either way, that receiver is now marked and I am debating whether to send it to Futaba for post mortem, or smash it with a hammer. The last time I send a receiver in for an antenna replacement it was $60, so I may as well just buy a new one instead.

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Flying

I was quite anxious to try these new 55C Lightning packs in the SHP. I think this is going to be a big battery for Thunder Power simply because so many guys stepping up to a balsa 3D plane already have 3s 2200 packs from their Mini Ultra Sticks, Mini Pulses, Visionaires, T28s, and similar planes. When they need new packs they can get a high performance Thunder Power lipo for $36.99.

Right away I knew I was in trouble with the motor. As soon as it spooled up to full throttle I could hear the bearing were damaged. This did not show up on the bench, but then again, I don't run the motor up full throttle in the garage with a prop on the plane. Power was still very good, though I know the 2814 well enough that I am convinced a healthy one is capable of more. Still, I think even this much performance is enough for most people.

I am getting a list of parts together for all my other planes, and I plan to pick up some bearings. I've damaged bearings before and they are relatively easy to change out. The biggest headache is the little C-clip on the backside of the motor. If you don't have the right tool for that you will either never get it off, or it will snap in a fashion that sends it flying into that place where lost things go. I really need to just go buy the right tool for the job. That or stop driving my motors into the ground.

Still, even a damaged 2814 flies pretty well. This one just doesn't have the same edge it had before, but then again, we know who's fault that is.

The first three videos are when I flew the plane with the bad receiver. You can see me struggling to be precise with it, but the trim kept changing and every so often the elevator would just plain glitch. In the last video I got everything right and now she flies rock solid.

The SHP is just like I remember it. Right away I was on it and flying it like it was my primary plane. I've been without one for awhile and it's really great to have another one. I just need replace the bearings in the motor and it should be golden.

Just like with my 6s 3300 Lightning packs, I am delighted with my 2250 Lightning batteries. After handling those monster 6s bricks, these little packs sure seem dainty. I usually take four 4s packs to the field, and it is surprising how much lighter my flight box is when I take the SHP and it's 3D packs.

EDIT: With the elevator glitching it was impossible to get the CG dialed in. Once I changed the receiver the battery ended up about an inch behind when you see below. Every plane is going to vary a little, but that's where my last one ended up too.

I believe that since last flying an SHP, I have grown to like the planes a little bit more tail heavy than before. This is pretty close to neutral, though I am still moving it a 1/4" at a time. when I get it too far back I will move it to where it was the flight before and mark the location on the tray with a sharpie pen.

I knew I could not resist flying this plane hard, so to take it a bit easier on my brand new packs, I settled in on a 4 minute timer. I was coming down with more than 11.5 volts in the pack every time. You want to stop before 11.1 volts, so this is a good margin., I am guessing I will be able to fly the plane really hard for five minutes and not run the pack too low.

Even with the motor struggling with bad bearings the Lightning packs still performed very, very well. Just like it is right now, the plane has just about the perfect balance of. I replaced the motor for the last video and you can see a pretty big difference, but again, power is still in that 180-220 watts per pound range that gives you really easy 3D control.

Lower C rated batteries tend to be a little more stable than high C rated. For example, I could run my 15C packs down to where it hit the low voltage cut off every single time and those things lasted forever. Not knowing any better at the time, I over amped them until they were too hot to touch, repeatedly, and they still held up. On a 70C pack you might get away with that once or twice. but they live longer if you treat them better. Once I started taking better care of my batteries had much better life expectancy and reliability.

The 70C batteries are almost bulletproof, so I am expecting these 55C packs to be like Vampires and never die, as long as I treat them with a reasonable amount of care. So far, power is really, really good, though not what I have become used to flying 4s for the last five years. It was a bit of an adjustment at first, but once I got a feel for the different power to weight ratio it was no problem. You just have to be a little quicker on the power and stay ahead of it better. It's not harder. It's easier in fact, though you do have to adjust your style a little.

I went to 3s on this plane for a reason. This plane flies exceptionally gentle on 3s and is almost painfully easy to fly, which is exactly what I want from it. It's designed to be that way so it can be a perfect first 3D plane.

But, back to the Lightning packs, so far I could not be happier, especially considering I still fly a high performance Thunder Power pack, have a great warranty, and saved a lot of money on them.

For now there's not much else to say other than it was great to have a nice, cool day that I could enjoy to test a new plane. It rained right when I got to the field, but SPARKS dries fast. The overcast stayed all day, which not only kept the sun out of our faces, but the temperature stayed cool. Being this is the middle of Florida Hell Days in July, the beautiful day was a wonderful surprise. We just had to dance around the puddles for a few flights and then it was perfect.

This is the flight after I changed out the receiver and you can see how locked in the plane is now. I also found a spare Torque 2814 I had forgotten about and installed that. The motor made a huge difference as you can see in the video below.

I plan to be flying the SHP exclusively until the 44" Slicks get here, so stayed tuned for whatever good or bad misadventures I can have with this plane. If history is anything to go by, it should be nothing but fun.